1. Field of the Invention
The present invention relates to a motor and a recording disk drive device, and more particularly, to a motor that can ensure the rigidity of a hydrodynamic bearing as well as minimize power consumption during the driving of the motor and a recording disk drive device including the motor.
2. Description of the Related Art
A small-sized spindle motor, used in a recording disk drive device, includes a stator having a coil wound therearound and a rotor rotated by electromagnetic force generated by voltage applied to the coil.
Such a small-sized spindle motor uses a hydrodynamic bearing assembly. While lubricating fluid is interposed between a shaft and a sleeve of the hydrodynamic bearing assembly, the shaft is supported by fluid pressure generated by the lubricating fluid.
In a case in which a gap between the shaft and the sleeve narrows, the rigidity of a hydrodynamic bearing, generated between the shaft and the sleeve, increases to thereby achieve an increase in the stability of the motor. In this case, however, power consumption used for the rotation of the shaft increases.
Therefore, the provision of a motor that can ensure the rigidity of the hydrodynamic bearing while minimizing power consumption is required.